The present invention is directed to prefabricated concrete units that are easily manufactured, transported and assembled at any site. The units can be arranged to form a cemetery in the form of either a high-rise mausoleum or a complex of mausoleums. A seal is defined by a gasket or similar material which forms a perfect airtight seal for a crypt compartment, thereby eliminating the requirement for ventilation and/or drainage in the crypt compartment.